The only problem with Walmart is they will only put the same size tires that originally came on the vehicle, according to the sticker on the door. I've run 285s on my truck since '05, and the last time I went in, they wouldn't put them back on, even though they had before.

For alignments, I go to Makloski's on Elm street. He has been very honest with me, and there have been a couple of times he told me I didn't need an alignment and didn't charge me for checking it. He sells tires as well, but some he can not warranty.