You can learn to drive a manual transmission when you buy a new car with one
In that price range you have a plethora of options, my friend. Especially being in Canada, you have the option to buy imported Japanese sports cars, which opens up your options even moreso! Here's a list of cars I'd consider; take the time to research them and see what grabs you!
Toyota: AW11 MR2 Supercharged (Super Charger in Japan) - owned and loved it!
SW20 MR2 Turbo - owned and loved it!
ST205 Celica GT-FOUR
MA70 or JZA80 Supra Turbo - driven MA70 and enjoyed it!
Nissan: Z32 300ZX (Fairlady Z in Japan) or Z33 350Z
S13 or S14 240SX (180SX or Silvia in Japan) - driven a few, lots of fun, lots of support and cheap to keep on the road!
R32 or R33 Skyline GT-S or GT-R (GT-S is RWD, GT-R AWD) - my unicorn
Mazda: NA or NB MX-5 Miata - an absolute blast to drive!
FC3S or FD3S RX-7 - owned FC3S, loved it! FD3S is the sexiest car ever built IMO
Honda: Civic/Integra - need I say more?
AP1 or AP2 S2000
Subaru: Impreza WRX - driven several, very easy to drive and make more power from. Like the new generation's Civic
Mitsubishi: Lancer Evolution I through VIII
3000GT VR4
Ford: Mustang (pick a year, any year)
Chevrolet: Camaro (pick a year, any year) - had a couple, fun and cheap
C4 Corvette
Audi: B5 or B6 S4 - driven a couple, luxurious and fast. B5 has 2.7L TT V6, B6 has 4.2L V8
B6 or B7 A4 2.0T
VW: Golf GTI
BMW: E30, E36, or E46 3-series - E30 is a focused driver's car. E36/46 are more refined
The list goes on and on and on... I'd pick up a copy of Gran Turismo IV or V and drive a bunch of stuff, then see what applies to that sub-$20k range.