Before shopping for Rams Tickets, expand and print this map of the Dome.  It's always nice to know the physical location of your seats before you spend your hard-earned cash.  End-zone, upper-deck seats (for example Section 427) are considered "cheap seats."  The best seats are located in the lower-level near the 50-yard line like those in Section 113.

The Dome has 4 distinct levels:
Level 1: Field level seating - the RED and YELLOW areas on the map. Sections are numbered in the 100s. In the RED area, rows are lettered sequentially A, B, C, D, etc. Game visibility is somewhat impaired in the first 10 or so rows off the field but you are more likely to be seen on the Dome Jumbotrons or national TV. In the YELLOW area, rows are lettered sequentially AA, BB, CC, DD, etc.  The YELLOW area will usually give you a very nice view of the game.
Level 2: Corporate boxes (not shown on map).
Level 3: Club seating - the BLUE area of the map. Nicer seats and special food service. Sections are numbered in the 300s. Rows have single letter assignments: A, B, C, etc.  Club seating is the best seating in the Dome.
Level 4: Terrace level - the GREEN, PURPLE, and PINK areas on the map. Terrace level sections are numbered in the 400s. The GREEN area is known as the Terrace Loge aka "Poor Man's Club Seats." There only 5 rows In the Loge area and the rows are lettered A thru E. In the PURPLE and PINK areas, rows are lettered AA thru XX. If you find yourself with a Row XX seat, better bring a good set of binoculars!

FREE tickets are always best.  Ask your family, neighbors, friends, employer, fellow tailgaters, etc if they have any extra tickets.  You may just get lucky!

The next best source of Rams Tickets is the Rams Ticket Office.  However, since most home games are sold out weeks in advance, buying tickets during football season directly from the Rams Ticket Office is not very likely.

Try the St Louis Rams Ticket Exchange: RamsTix.com.

The St Louis Post-Dispatch often has Rams Tickets for sale in its Classified Ads Section.

Another good source of Rams Tickets is Ebay.  Ebay is a worldwide online auction service.  During football season, there are usually lots of Rams tickets for sale on Ebay.

As a last resort on game day, tickets are sold by "street scalpers" outside most entrances to the Dome.  The most active location is Entry B which is at the Southeast corner of the Dome (the intersection of Broadway St and Convention Plaza).  Bring cash.  MasterCard & Visa are not accepted.  Keep in mind "street scalpers" are working under "kickoff pressure."  If you can wait, ticket prices drop like a rock after kickoff.