"I Just Bought My First SNES!" or "Super Mario: The Red Menace!"
 

It and a game (Super Mario World) cost me a good sixty bucks.

What other games should I look for on Amazon?

Super Metroid.

some initial suggestions
 

Illusion of Gaia and Inindo: Way of the Ninja are both pretty good. Well, I'm gonna have to hedge on Inindo a bit since it's not for everyone. The music and graphics are NOT up to snuff for a SNES era game, but it's got a cool mix of RPG and strategy elements as well as a fairly crazy amount of freedom in how you go about accomplishing the plot.

As for Illusion of Gaia, I don't have to hedge on that at all; it's just a pretty badass example of SNES adventure games. Also, the music, man... the music.

What I've Got So Far
 

Oh, add Megaman X to that list!

In the same vein as Illusion of Gaia--you might look for Soul Blazer, which is sort of spiritually related to it. Kirby Super Star is also tons of fun, as is almost any of the Donkey Kong Country games.

Also, I don't know if you'll find it, but if you run across a reasonably-priced copy of EarthBound, snap it right up. It's worth every penny.

Another game related to Illusion of Gaia is Terranigma, it didn't get released in the US, but did get a European release.

Also, if you like Secret of Mana, you should check out Secret of Evermore.

THe beautiful thing about the SNES is that you can get your hands into some pretty cheap stuff if you like to play around with weird and little known games.

Thanks to Game Grumps i can suggest SkyBlazer to things you would like. As well as Demon's Crest. Pilotwings is neat too.

Rock n' roll racing
Teenage Mutant Ninja Turtles IV: Turtles in Time
Super Mario All Stars (will conclude your mario fix)
Contra 3
Megaman 7
Super Castlevania 4
Super Punch Out
Donkey Kong Country
Yoshi Island
Sunset Riders

that should set your SNES collection. But please, give yourself the gift of gaming by hitting ebay and picking up some cheap games with cool covers from all over the world.