Do boosters stack? As in if I were to buy a 200tc booster and a 50 tc booster would that work as 250tc?

As far as I know, boosters will not stack.

I believe I tried this once a year or two ago. It may have changed since then (not likely), and I don't think they stacked then. If I remember correctly, the one that gives the most output per game is the one that takes effect. This was two years ago, however, so it's possible that this changed.

Here's your final answer.

[6/11/14, 7:32:11 PM] Risk: Pretty sure they don't stack.
[6/11/14, 7:32:23 PM] Twi: yeah, that's the conclusion i came to
[6/11/14, 7:32:36 PM] Risk: Not positive though actually.
[6/11/14, 7:32:53 PM] Twi: is there a way for a wizard like you to check?
[6/11/14, 7:33:17 PM] Risk: Nah, I'd have to see the code to say and I don't have access to that.

Nope you can stack them, thats why its better to buy Once at a time