In the EA Fact Book (at least, as it was when I submitted the manuscript to Mongoose...they may have changed it for all I know), blip is not a prestige class, but a separate class from telepath. You CAN multiclass into blip, but you cannot be a multiclass blip/telepath. Blip is a dangerous class to play...if Psi Corps catches you, they send you to a reindoctrination center, mess with your head, and you come out as a 1st level telepath with most of your old personality gone. Blips gain telepath feats less quickly than telepaths, and their max P-rating is limited by their level since they have to train themselves. However, they are adept at hiding their telepathic abilities (psychic stealth), pick up patrons who help hide them from the Corps, and can employ mind bursts as a desperation move in the event of certain capture. If you want to play a human character who's hiding his telepathic abilities from the Corps, you play a blip.
Also, just to keep your appetite whetted for this book, there are telepath prestige classes for the black ops specialist (they can become "invisible" by making people just not notice them), bloodhound (telepath hunter), teek (move stuff with your mind), telepathic monk (uses psi abilities to enhance his own body), and psi experiment (a result of PsiCorps modifications, you receive random and unpredictable powers and flaws...you can even evolve into godhood).