My mechanic tells me I need a drive belt & tensioner assembly. Cost from him:
Drive belt = $44
Tensioner Assembly = $114
Labor = $152

I'm trying to find these parts online to save money. I think I can find the drive (serpentine) belt. But I don't want to buy the wrong tensioner assembly. It needs to be for the drive belt, not timing belt. Whats the best place to look & what keywords are best?

What brand is the best to get? AC Delco? Dayco? Gates?

I can't install it myself, so is this a decent price for labor? In the Atlanta area.

BTW, its an 2004 TSX w/ 90k miles

rockauto.com has them for anywhere from $45 - $68 plus shipping. They also have belts there as well. But keep in mind some mechanics will give you a better labour price to compensate for their higher parts prices... check if the labour is the same for customer-supplied parts. Also they might not warranty their work on parts they don't supply to you.

Gates / Delco / Dayco are all good brands.

This past winter, I changed out my OEM auto tensioner and drive belt. Replaced them with Gates products bought both from rockauto. Parts were belt @ $24, tensioner @ $40, labor free since I did it. I bought a tension release tool from Sears for $20 which made the job so much easier; and I used my existing tools. The toughest part was getting the auto tensioner out since one of the 3 screws holding it in is at a cramped area where there's little room for my hand to get into.

You don't need the tensioner release tool... just use the double-wrench method (one wrench on the bolt, the other attached to the other end of the same wrench to provide additional leverage).

JTso has a good pic of how to do this method from one of his many informative posts:

Right, not absolutely necessary. But if you like getting new tools, like me, then get it.