Get your PC7424 on Coastaltool.com
. That will take care of about a hundred and twenty of it. Most of the rest of it you can get locally, but you will want to order a couple pads online. They pretty much cost the same everywhere, but Autogeek.net is where I shop for most of my stuff, so I'll refer you to them. Get a red pad and a black pad and that should take care of your polishing and waxing needs. Maybe pick up a couple microfiber towels while you are at it. I'd say you could go through maybe $50 bucks on Autogeek stuff.
As far as waxes and polishes go, thankfully there are some good options locally. Meguiar's Ultimate Compound and the Ultimate Liquid Wax are both products I'd recommend. Those will run you about $30 bucks for the pair at any AutoZone. A bar of clay will cost you maybe ten or twelve bucks. CD2 Engine Detailer is $5 at AutoZone. Eagle One Wheel & Tire Cleaner is about $5 bucks. Same with the Eagle One Wet tire shine. You might want to get yourself a couple tire swipes for applying the shine, so that will be another couple bucks. Don't forget the Invisible Glass for your windows and maybe Meguiar's Quick Interior Detailer for a quick wipe down solution on your interior. Those both run between $5 and $7 a bottle.
If you have leather then you will want to get your leather product online. I haven't found a good one off the shelf. Pinnacle and Wolfgang both have awesome leather care products on Autogeek. I'd recommend either of those. They are kind of spendy, but man are they worth it. If there was an 'over the counter' solution for leather care then I would be all over it, but so far I haven't used anything I would recommend.
That should just about do it. Maybe a $5 can of Tuff Stuff if you have some carpet spots to clean and a $5 bottle of engine degreaser if there is cleanup to be done under the hood, but those are the products I'd suggest if you are looking to put together a decent detailing collection. Other than the pads, towels, and maybe the leather care products, everything else can be found at AutoZone. CD2 Engine Detailer is likely ONLY found there, but everything else could probably be found at WalMart or any other store with a car care aisle.