Not sure why people are saying it is tricky, the V402 ide68k hits the spot. It's not that expensive and can be bought new via the Amibay link I provided.
There's plenty of support too on how to set it up etc.
Plenty of side cars are available too, just have to visit the market place here or check out amibay there's items always being listed.
My a500 plus is currently setup with an a590 with 7.0 roms and a SCSI card reader I picked up through mechware. All very good prices too.
If you come across a a590 without a PSU don't panic, 1) you can mod the A500 or 2) buy a cheap atx adapter from amigakit.
I also just remembered that tomthul via Amibay has a non autoconfig cf card/RAM solution too which comes with a floppy disk to boot and use it, so that could be another option.
The hardware is there, links are provided just need to ask the people that make the hardware and you will receive.
The A1200 is easier, you can pickup cf cards and adapters really cheap. Or even IDE laptop hard drives will suffice. Which they originally had installed. All very cheap.
Accelerators, turbo cards are everywhere too for the A1200. Jen's can be partly thanked for that. But then you get into another issue with timing problems which apparently are a fault with the 1200. Which I recently found out about first hand.
The only hard thing I've found with the A500 is finding accelerators for it, people hang on to them tightly and when they do sell it is for a rather high price. They're also under powered in most cases.
I was lucky and found a broken one that Amigakit was able to repair for me.
Anyway if you just want games then a 2MB A500 plus with a floppy emulator will suffice. Although after I played with WHDLoad it makes a huge difference.
@Lurch - that's a great tip about modding the A590, I recently started looking on ebay.de and found several of them (the regular North American ebay.com hasn't had a single Amiga 500 hard drive in months). Unfortunately I don't read German so no idea if they're working or not, might have to run it through Google translate, but knowing that I could mod a PSU is a great help.
On the other part, you keep mentioning links on Amibay. Not trying to open up a can of worms here, but I sort of have a thing against heavy-handed, ham-fisted moderation, and have heard enough horror stories about people being banned for accidently asking a question in the wrong place, etc., that I'd rather not register on that site. Besides, the prices I've seen just skimming don't look any better than sites like ebay. I realise I'm shooting myself in the foot and limiting my own options (although I didn't see any A500 hard drives there, either), but would prefer to buy hardware from a dealer such as AmigaKit, or a site like ebay (that has at least a limited form of buyer protection, etc.). Just my .02 cents!
