I triied one of these calculators (like iVolatility) and all it did was tell me that the option call was worth 78 cents. How do I use this and all the greek letters to calculate what would be the option price in theory after 2 months if the stock price reaches the strike price with 5 more months to expiration? The reason I want to know is if the cost to buy back the call is 2x the original cost I'm ok with that but if it's more I'm not.

Go to one of the BAC leverage threads. I posted a sheet with calculations of the warrant prices at certain price/expiration points. Use the formula in the sheet to calculate option prices - inputs are: Stock price, strike price, interest rate, dividend yield, volatility and time to expiration. The last parameters is probably what you want to play with to simulate what happens to the price when you roll time forward. No need to do it via the Greeks and much more accurate (since the Greeks change themselves as any of the other variable change ... e.g. theta = time decay speeds up over time/with less time remaining).

Actually - on second thought - sheet attached.

C.