I agree this is something we should be placing greater emphasis on. We probably have to "convert" several people for every one that will actually make it to the primaries to vote. Young people in particular may have never voted before and won't be familiar with the process of registering and finding their local polling place.
Here is a state-by-state list from Wikipedia that might be helpful. It's probably easier to read at the original source here with the formatting intact:
http://en.wikipedia.org/wiki/Primary_elections#Primary_systems_state-by-state
2011
In California, under Proposition 14, a measure that easily passed, traditional party primaries will be replaced in 2011 with wide-open elections.
2010
Oregon became the first American state in which a binding primary election was conducted entirely via the internet. The election was held by the Independent Party of Oregon in July, 2010.
2008
For information about a particular state's primary system as of January 2008, see list below. The best source of up-to-date information is often the official website of the state in question, but this can be hard to find. For example, California lists detailed information about its current "modified closed" (i.e. semi-closed) system on the California state website. Similarly, information on the Arizona semi-closed primary system can be found on the Arizona state website. For Presidential candidate delegate assignment, however, Arizona conducts a Presidential Preference Election (PPE), distinguishing the contest from the state's primary election laws. Arizona's PPE is closed to those not registered with a state-recognized party.
* Alabama - Open Primary (Feb 5). Deadline (10 Days - Jan 26).
* Alaska - Caucuses (Feb 5). Deadline (30 Days - Jan 6).
* Arizona - Closed PPE (Feb 5). Deadline (30 Days - Jan 6).
* Arkansas - Open Primary (Feb 5). Deadline (30 Days - Jan 6).
* California - Semi-Open Primary (Feb 5). Deadline (15 Days - Jan 22).
* Colorado - Caucuses (Feb 5). Deadline (29 Days - Jan 7). (For Democrats, the deadline to register is Feb 5)
* Connecticut - Closed Primary (Feb 5). Deadline (12 Noon, Feb 4).
* Delaware - Closed Primary (Feb 5). Deadline (24 Days - Jan 12).
* District of Columbia - Primary (Feb 12). Deadline (30 Days - Jan 13)
* Florida - Closed Primary (Jan 29). Deadline (29 Days - Jan 1).
* Georgia - Open Primary (Feb 5). Deadline (Jan 7).
* Hawaii - Open Caucuses (Mar 2). Deadline (30 Days - Feb 1).
* Idaho - Open Primary (May 27). Deadline (May 2 for pre registration. Registration allowed on Election Day).
* Illinois - Semi-Open Primary (Feb 5). Deadline (27 Days - Jan 9).
* Indiana - Open Primary (May 6). Deadline (28 Days - Apr 9).
* Iowa - Caucus (Jan 3). Deadline (10 days - Dec 24, 2007).
* Kansas - Caucuses (Feb 9). Deadline (15 Days - Jan 25).
* Kentucky - Closed Primary (May 20). Deadline for new registrations (28 Days - Apr 22). Deadline for party switch (Dec 31, 2007)
* Louisiana - Caucus (Feb 9). Deadline (Jan 11).
* Maine - Caucuses (February 1 through February 3). Deadline (None - Day of Election though check the rules regarding this caucus).
* Maryland - Closed Primary (Feb 12). Deadline (21 Days - Jan 22).
* Massachusetts - Semi-Closed Primary (Feb 5). Deadline (1 Day - Jan 16).
* Michigan - Open Primary (Jan 15). Deadline (30 Days - Jan 6).
* Minnesota - Open Caucuses (Feb 5 *). Deadline (20 Days - Jan 16).
* Mississippi - Open Primary (Mar 11). Deadline (30 Days - Feb 10).
* Missouri - Open Primary (Feb 5). Deadline (4th Wednesday Prior - Jan 9).
* Montana - Open Primary (Jun 3). Deadline (30 Days - May 4).
* Nebraska - Primary (May 13 *). Deadline (Second Friday before an election, May 2).
* Nevada - Caucuses (Jan 19). Deadline (30 Days - Dec 20, 2007).
* New Hampshire - Semi-Open Primary (Jan 8). Deadline (10 Days - Dec 28, 2007).[9]
* New Jersey - Primary (Feb 5). Deadline for new registrations (21 Days - Jan 15, 2008). Deadline for party switch (50 days - Dec 17, 2007). Unaffiliated voters can declare on the day of primary.
* New Mexico - Republican Primary (Jun 3). Deadline (28 Days - May 6) Democrat closed caucus Feb 5, 2008 (deadline January 4).
* New York - Closed Primary (Feb 5). Deadline (25 Days - Jan 11).
* North Carolina - Semi-Open Primary (May 6 *). Deadline (30 Days - Apr 6). Early voting starts April 17
* North Dakota - Open Caucuses (Feb 5). Deadline (No registration. Must have residency for 30 days - Jan 6).
* Ohio - Semi-Open Primary (Mar 4). Deadline (30 Days - Feb 3).
* Oklahoma - Closed Primary (Feb 5). Deadline (24 Days - Jan 12).
* Oregon - Closed Primary (May 20). Deadline (21 Days - Apr 29).
* Pennsylvania - Closed Primary (Apr 22). Deadline (30 Days - Mar 23).
* Rhode Island - Primary (Mar 4). Deadline (30 Days - Feb 3).
* South Carolina - Open Primary (Jan 19 for Republicans, Jan 26 for Democrats). Deadline (30 days - Dec 20, 2007 for Republicans and Dec 25, 2007 for Democrats).
* South Dakota - Closed Primary (Jun 3). Deadline (15 Days - May 19).
* Tennessee - Open Primary (Feb 5). Deadline (30 Days - Jan 6).
* Texas - Semi-Open Primary (Mar 4) & Closed Caucus (begins Mar 4, schedule based on party rules). Voting in primary is prerequisite for caucusing at precinct convention, which convenes after primary polls close. Deadline (Feb 4, 2008).
* Utah - Closed Primary (Feb 5). Deadline (30 Days - Jan 6).
* Vermont - Open Primary (Mar 4). Deadline (Feb 27, 2008).
* Virginia - Open Primary (Feb 12). Deadline (29 Days - Jan 14).
* Washington - Open Caucus (Feb 9) & Primary (Feb 19). This is a two step process. Deadline (30 Days via mail or online, 15 Days in Person Friday, Jan 25).
* West Virginia -Closed Primary (18 Delegates at the State Convention on Feb 5 (ask the state party for details), 12 Delegates for the May 13 Primary). Deadline (21 days to register or change your party to Republican - Apr 22 for the Primary).
* Wisconsin - Open Primary (Feb 19). Deadline (The day before or the day of at your polling precinct).
* Wyoming - Caucus (Mar 8).
* - Note that these Primaries / Caucuses may be changed to a date earlier than stated.
