DPS, Spell, Cooldown, Casting Time Timer

Is there a tool for determining casting time, cooldown time, and other spell cooldowns, without having to do a shit ton of math? Currently I'm using paint, with the ruler on, and copy and pasting lines that represent spells, with their casting time if any, and cooldowns on a seperate line. I am doing this cause currently my macro for my shadow priest is stopping between casting mind blast spells, so I'm figuring out a good rotation to have. But if theres a program, or excel sheet, I would love to use that instead.

excel is good as is powerpoint. For excel you could make each cell .25 seconds so a 3 second cast = 12 cells... or something similair to line out where your spells are... So I would probably use Excel... I hit a few dead spots in my macros as well.