This is a classic "catch 22." You want to focus on your triceps, so you exercise the fuck out of them. Trouble is, they are such a small muscle group, you wind up with them staying about the same no matter how hard you hit them. Solution? Combine them with a larger related muscle group (like chest.)
Go to THE Home Depot and have them cut you a 4X4 down to about 2 feet long. (Yes, we're talking lumber here.) Throw that sucker in your gym bag. Next time you work chest and triceps, slide that 4X4 under your shirt and lie down and do some close grip bench presses while the 4X4 is under your shirt. When you get to the bottom, allow the bar to come to a complete stop on that 4X4 and let it rest there for about 3 seconds. Now make that bar quickly explode off your chest. Remember this is CLOSE GRIP presses. You will need to lighten the weight at first until you get used to it. Your chest will assist your weak-ass triceps in lifting this weight, but your triceps will be forced to do most of the work. Oh, and keep your elbows to your sides! Otherwise your chest will help too much.
Now lie flat on the floor (or bench) and get out the E-Z Curl Bar. Start out light. Do some skull crushers. Keep your elbows pointed at the ceiling and keep those fuckers still! Go light at first or you won't be able to jack off for 2 weeks.
Now do some cable push downs, but make sure you put these closer towards the end of your workout as you want to do the mass builders first.
Finish off with some bench dips. (Hands behind you on a bench with your heels on another bench.) Body weight will be sufficient at first. Then start adding a plate in your lap.