"i don't think college coaches look for fastballs around 90 mph although i think it's a nice bonus. the fact is that throwing 90+ is really hard and I'd bet that the majority of DI pitchers throw less than 90 (save for ones at the top baseball schools in the country)."
At the University of North Florida the avg. velo is mid-eighties, don't think that they don't look for velocity, they do, 90's just really aren't that common, they also look for many of the following things; Grades...forget D-1 if you don't have great grades, core scores and your SAT/ACT(Waivers are available..but you better be top 10% in the country or better). Health/Projectability...if you are maxed out at 5'6" and 120lbs you may not get much of a look without some one of a kind skills. Work ethic...which can be displayed by exraordinary grades, additional college level class work (Honors classes) and community service. Performance, you may be on a team that stinks in your district, but how did you perform when you got the ball (Scouts know...believe it). Endorsement/recommendations, having someone like a coach back you is a major thing, don't over look it..I'm not saying be a suckup, be a person with integrity and values, someone who is easy to get behind.
Be coachable...college coaches will not deal with an attitude or a know-it-all.
Step back and look at what i just wrote, quite a lot has little to do with baseball..a whole bunch has to do with being a quality person..they want success, because feeding their families depends on the choices they make. If you approach it that way your road will be just a tad bit smoother.