The best resource that I found and used was Dan Steven's best man speeches . It's not free but well worth it, I'll explain why...
Most of the free best man sample toasts on the net are largely unoriginal and tacky, I wasted a lot of time going through all that. I felt that with a task that would be "judged" for many years it would be worthwhile doing a proper job.
With the best man speeches site I received instant access to many different best man sample speeches and toasts for most situations and occasions. You can use the solid structure they provide and then personalize your speech and make it your own - add some of your own personal stories and anecdotes.
The speech will take about 45 minutes to an hour to prepare, a big relief!
I received many compliments and was told by many that my speech sounded very professional. The guests loved it, I was very happy with the result and my preparations.
Good luck!
