Firing of fast twitch muscles is not dependent on the speed at which they contract (which you would assume by the name) but by the force which is required to move the load present. When you sprint, you are moving faster than when you jog, so the total force required is higher, thereby requiring the use of higher-twitch muscle fibers. When lifting a maximal load (any load that is moving at maximum speed; this load is not being intentionally "slowed down" at all) will cause fast-twitch muscle fibers to contract, not slow-twitch, even though the movement may often seem slow.
Fartlek isn't optimal for developing fast-twitch muscle fibers because it won't cause those at the upper end of the threshold to fire because you never reach maximum exertion using Fartlek methods.
Bill starr's would be great for building up a base of strength, but squatting 3x a week + optimal speed training probably isn't possible unless you are a very highly conditioned sprinter. The idea with Bill Starr's would be that you use it in the offseason to build strength, then as you transition to preseason, you switch to a program with a little bit less volume and maybe a little more variation so that the sprint training isn't impeded (at this stage you are working on taking your strength and increasing your rate of force development, and therefore your weight training should not interfere at all with your sprint training, for optimal results.)
I'd recommend trying to design a program that has you lifting twice a week using the big compound movements that you like, as well as one day devoted to plyometrics (assuming you have a decent base of strength; if not, it may be more beneficial to use this day for extra agility drills or another day of lifting.). Use the other days for rest or agility drills. Just remember when designing a program that you can try it out and if there isn't enough work in it for you to see progress, you can always just add in another set of something or another exercise; as long as you obey the overload principle you will see progress somewhere. For it to be speed, you'll probably be looking at increasing the % of your 1rm that you work with or increasing the load on your plyometrics by increasing height/depth.
Edit: don't be afraid to spend a little money on a book. Go to half.com and search for the book you're after, and you'll usually find something lightly used in the $3-7$ range. I picked up a virtually new copy of Power Training by Robert Dos Remedios (per recommendation of Ano) for $7, $10 shipped. (by the way, Power Training looks to be an amazing program. I've only just started it but I literally got my ass kicked the first day and got DOMS for the first time since I started lifting. Anyone would have ZERO trouble obeying overload with this baby.)
