Hahaha, come on guys. Why don'cha give him a strategy that works?
Listen buddy, all you really need is one tech an alien race doesn't have, a couple spare bucks, and a high diplomacy rating. Boost it with your basic race beginning. Don't even consider trying to out-tech the AI - it's not going to be easy.
Giving them a basic tech, however, for one of their basic techs is only the beginning. Then you go to another race, trade the same basic tech for a new one - then the next race and so on and so on. The AI does this too. Your advantage will be your high diplomacy rating giving you ridiculously nice deals.
Not only will you have every tech that they've ever researched (it's ridiculously easy and you never need to give up anything substantial), but you'll have a ton of techs that only you and one or two other races have - and then the ones you specifically research, usually to improve your diplomacy.
Seriously, give it a shot. Were that not enough a high diplomacy rating also nets you a handy little relation bonus to other races: They won't consider invading you nearly as soon as they would without it.
And one last time, say it with me now: Don't try to out-research the Aliens. Let them do the hard work while you sit back and buy it from them later.