I'm not usually a brand loyal kind of guy, but for some reason I have this thing about always buying Timken bearings. That Autozone is a distributor, only supports this sillyness. Also a fan of national seals, but I have been known to run whatever will get the vehicle back on the road the fastest.
As was mentioned, If your bearings are bad, so are your seals. I would hazard a guess, that for your bearings to actually be bad at 110K, the seals are bad and the axle is low on fluid. Be careful though, the axles wear also and depending on how long the bearing has been bad, may also need replaced. Good condition used axles can be found for much less than new, if that is the case.
If you are just doing the outer seals and bearings, you can easily do it in a weekend, and probably only a day in most cases, with a slide hammer and the three jaw puller attachment. There are other ways to remove the outer race, the fastest and easiest is to just rent the slide hammer set from the parts store.
EDIT: Is it possible that you just need brakes? Squealing is not a sound normally associated with bad wheel bearings. However brake pads have a little metal finger that is designed to give you a metallic sounding squeal when your pads get worn. Oddly, they are referred to as squealers.
EDIT again (trying to avoid a double post): Two more things. A roaring noise is more typically used to describe the noise from bad wheel bearings. Ever had a tool or toy with a "rough" bearing or two? That noise amplified, is what a bad wheel bearing typically sounds like.
Also, I am not saying that your front hub bearings aren't due for replacement, but if they aren't loose (you cant rock the wheel in any direction when it is off of the ground), then replacing them is almost wasted money. There is also a trick for greasing them that supposedly helps them last even longer.
