I got my Saturn from eBay about four years ago by now, but back then it was an outstanding deal even though the average around the time was $30. I spent $30 myself ($20 + $10 shipping) but I ended up with the following:
Sega Saturn w/ Power Cable and RF Switch
Two Controllers
Daytona USA
Virtua Cop
Sure, not necessarily amazing, but if I can hook it up and start playing two-player games right out of the box it's well-worth it. Seller was really nice as well, updating me every step of their way and really did a bang-up job of packing. One of my best eBay experiences, bar none.
Otherwise, it depends. I know in Pittsburgh The Exchange had Sega Saturns in every so often for $30. They were always tested, though, and always came with a controller and all available hookups, although sometimes you would get a component cable rather than an RF Switch (made the deal sweeter, really). Still a bit much for the money but they made up for that by charging around $1 to $5 for most Saturn games, with the real classics going for reasonable prices (NiGHTS w/ 3D Controller = $10).
Personally, I say follow the usual eBay tips of watching good sellers and just waiting for a price/package you really want and think you can get for a song. It may take some time but, hey, sometimes you really luck out.
[Edit:] Of course, there are always those CAGs who are selling their Saturns. They tend to go for around the same base price of $30 more often than not but they usually come with a whole lot more than what you would get on eBay. That and, since most people on here are really big on gaming, you can even get some costlier items like the 4 MB Pro Action Replay and Japanese imports for a whole lot less. And yes, that is a big deal if you want to play some of the best Saturn games for cheap. Oh man, do you save a boatload that way.