I've watched cartoons all my life and I'm not ashamed to say i've had plenty of crushes on toon characters. let's be honest, some of them are down right hot and people naturally feel different ways about different toons.
Just be warned, my list might be a tad long:
Frankie - Everyone knows this about me already
Fifi Le Pume - SOOOO dam cute, i never realized how much I liked her until I got older.
Gadget Hackwrench - One of my first toon crushes, easily see why Chip and Dale go gaga over her.
Bunnie Rabbot - That southern accent is down right adorable, I always thought she was such a sweetheart.
Misty - my first anime crush and one I still hold strongly today. Her appearance, her personality, there's just SO much to like about her.
Pilot Jenny - Bucky O hare character. Downright sexy and very different from other toon females, she was a very kind and interesting character.
Kari - Hottest Digidestined I ever saw and by far the sweetest, I'd date her in a digi-heartbeat.
Mahoro - Such a sweet and loving anime android, even if the anime is loaded with fanservice, I can't change how much I adore and love this character.
Princess Sally - Another Sonic cutie I had to mention. I think she's one of the most beautiful drawn characters in animation, always liked her, always.
Starfire - Titans made her look amazing, and so darn cute! I love her relationship with Robin and she's always been my favorite Teen Titan to date.
Kei - From dirty pair flash. Its weird but she's nothing like me, yet she's always been one of my biggest cartoon crushes. Very fiesty, very strong, and very cute.
Nadia - from the anime of the same name. It may sound weird for a white guy to be attracted to a toon black female, but its true. I think Nadia is a very attractive character and despite her temper, she's definitely a crush of mine.
Sailor Jupiter - One of my earliest crushes. I always felt Sailor Moon shafted Jupiter and never gave her enough air time, or centered episodes. i think she's a sweet, caring, and strong character who REALLY deserves that special someone.