Originally Posted by Motorolan
The Andover Shop in Andover or Harvard Sq.
J. Press on Mt. Auburn Street in Cambridge (Harvard Sq. across from Crazy Dough)
Andover Shop is a good suggestion (nothing against Press, just don't have experience). They definitely have a more conservative, preppy style, very different from Armani. Another option in Harvard Square is Rizzo's on Church Street. I've had him do some tailoring for me before on stuff that I bought off the rack, and his work is top notch. He is a little difficult to deal with (you need to be emphatic about how you want something to fit because he can be pretty insistent about what he thinks the right fit is, and trends toward a more European style, he also wouldn't work on a suit I brought to him that had been poorly tailored at Saks because he said he wouldn't clean up another tailor's mess, which pissed me off). He claims that John Kerry, the late Sen. Kennedy, and other local big wigs have had their suits made by him.
I've always had great luck buying suits off the rack at a high end department store, and then bringing them to a good tailor to be fitted (which is what I did for my wedding suit). It's usually cheaper than having a bespoke suit made and if you find a brand that fits you well I would be surprised if you could tell the difference between that and bespoke. If you go that route, do not have the dept. store tailors make the alterations, and leave the tags on because the tailor you bring it to may have some input on fit and you may want to change sizes or brands.
One final thought, I often look for Loro Piana fabric when I'm buying suits, sport coats or slacks. Many brand names use their fabric, and I've found that it looks great and holds up really well over time.