y'know, I was thinking the other as to what a friend of mine (r0jaws on AmiBay) once said to me.
Long gone are the days of a cheap Amiga experience, and you know I believe he is right to a degree. So with your question I had some serious thought on what would be the cheapest / cost effective I would suggest today to get into.
I would suggest the following two options -
A500+ (A five hundred plus) with the additional of
1MB CHIP RAM
Kipper's K508 8MB FAST + CF adaptor
8GB CF Card
You could probably get that lot around the $100 - $150, but this is a cracking system, you would have and be able to run 90% of Amiga games software, with a large storge and good amount of RAM to make it happen.
A1200 2MB CHIP
ACA1220 020@20MHz + 128MBFAST
8GB CF Card
This set up will set you back about $150 - $200 if you are frugal you might get it a bit cheaper. This system is roughly 6 times faster than the previous mentioned A500+ and for the most part play 98% of the games released for the Amiga, some older A500 games are not compatible, some other games require more processing power and or an RTG graphics card
but thats about the long and short of it