have you considered all wheel drive?
Here are some suggestions:
89-98 Nissan 240sx+Dirt Cheap
+Rear Wheel Drive
+Loads of aftermarket parts & Japanese parts to swap with everything from bolt ons to complete body and engine swaps available
+pretty unique (I rarely see them around)
-Hard to find (particularly in a stick about 80% of the autos)
-some models arn't the quickest/best looking when stock
STOCK:

With the Japanese S15 Front end conversion
85-96 Nissan 300Zx+Turbo Motors are fast
+Rear Wheel Drive
+If you look around you can find them for < $10K
+Some models have All Wheel Steering which is friggin cool
+next to the supra it's the epitome of import-tuner muscle
+Lots of aftermarket stuff available
-kind of heavy
-non turbo versions arn't the fastest (though still much quicker then your average sedan)
84-89 Mitsubishi Starion (AKA Chrysler/Dodge/Plymouth Conquest)+Rear Wheel Drive
+VERY rare
+Dirt Cheap (if you can find them) (the last one I saw for sake was only $1K

)
+Pretty Damn fast Turbo Motor
+Damn cool looking (kind of like a more boxy version of a Porsche 944)
-hard to find
-pretty old at this point
-not to many aftermarket parts due to it's age and rarity, though there are some you can import from Japan
94-99 Mitsubishi 3000GT VR4 (AKA Dodge Stealth R/T)+Damn Cool Looking
+All Wheel Drive
+Fast
+Decent aftermarket parts available
+Women love this car (I don't know what it is but ever chick I know swoons over them)
-usually a little pricey considering it's age (though still well within your range)
-depending on your area hard to find the VR4 / RT models
90-99 Mitsubishi Eclipse GSX (AKA Eagle Talon Tsi)+All Wheel Drive
+Awesome 2.0L Turbo Motor
+LOADS and LOADS of aftermarket parts
+Dirt Cheap
-Lots of people have the crappy GS version (non-turbo/FWD)
84-95 Mazda RX-7+Rear Wheel Drive
+Damn Fast
+Damn Cool looking
+Lots of aftermarket parts available
-Engines have a short life span if you plan on tuning them/beating on them
90-06 Mazda Miata MX-5+Rear Wheel Drive
+Depending on age well below or a little above your price range
+LOADS of aftermarket parts available
+Pretty quick
-kind of feminine looking IMO
-2 seater ragtop (could be bad or good depending on your tastes)
98-06 Subaru Impreza 2.5RS/WRX+even the low end/older models handle well (you can pickup a 02/03 WRX in your price range)
+lots of aftermarket parts available. If you get cash down the road you could even do an STi engine swap.
+All Wheel Drive
+/-02/03 models are kind of stupid looking IMO but 98-01 and 04-06 look pretty damned cool.
-only the older non-turbo (read: slow) models are available in a 2 door, all the newer ones are 4 door only
00-06 Honda S2000+Rear Wheel Drive
+Civic Drivers will kiss your feet wherever you go
+Damn Fast
+Bad-ass looking
+Loads of Aftermarket parts available
-probably a little above your price range
-2 seater ragtop (could be bad or good depending on your tastes)
91-05 Toyota MR2+MR2 stands for Mid engine Rear drive 2 seater, what's not to love
+AWESOME handling
+Loads of aftermarket parts
-kind of on the small side

You could also consider European... Porsche 944, BMW 3 series etc. All awesome RWD muscle cars.