Generate selling materials. That's just a fancy way of saying get headshots and cut a reel. Search for photographers online in your area. Find a few you seem to like. Then take the time to call and schedule a consultation. Things that should be discussed are price, number of shots to be taken and number of wardrobe changes. After reviewing the roles, make your favorite picture in 3 different styles in 8x10 inch headshots. Finally get multiples made. Also if you do have some previous acting experience, cut your work onto an acting reel. Repeat the search process that you had with photographer, except this time find an editor. Then make a DVD of your work (not longer than 6 minutes).
Join "IActor." If you belong to the Screen Actors Guild SAG, you can place those materials (reel and headshots) on their website along with your resume. If you are not a member of SAG, then you can join other sites that will help alert you of auditions for TV as well. Some of those are starnow.com or even instantcast.com. On those sites you will not be able to list your reel, but you will be able to place both your headshot and resume!
Read Variety. Variety is published during the work week both in Los Angeles and New York. (They also have a website at Variety.com.) Every Thursday, they list TV production charts in the back. Included in that info is the address and casting director of each TV show. Every casting office has a box in which you can drop off your headshot and resume. While it's still tough to get an appointment, often they call people in for smaller roles from those boxes. And once you get in front of a casting director, you have a great shot to make an impression!
Do workshops. A lot of casting directors in TV host workshops on the weekend giving tips on how to properly audition. Search craigslist or even a tradepaper called backstage (which primarily deals with theatre) for such workshops. This is a great way to get in front of the professionals and learn a thing or two. At the end of the workshop, be sure to give them your headshot and resume to keep for their files! Congratulations, you now have several steps to help get you acting auditions for TV!