Ive been playing for about a year now and have just got accepted into a band as a lead. I know the pentatonic minor and major but my improv is terrible, i need some blues and/or rock riffs that i could build on to make some less sucky solos

Please Help out a newbie
mmm... you can always try santana. really cool solos.. or joe satriani if ya want the crazy solos.
Learn Clapton's lead from the live version of Crossroads. You don't have to be able to play it at the tempo he does but there's a treasure trove of blues/rock pentatonic licks there. You can also take a look at this style analysis I did of Ace Frehley of KISS (http://www.geocities.com/acelessons/). Ace is a simple player but some of his stock licks, especially the way he uses rhythmic displacement, will go a long way towards sounding a bit more confident in an improvisation setting (since you can just pull up a few cool licks at will).