So next year in October I can apply for naturalization (I think). But...is there any certain time limit to apply, for example what if I wanted to apply in 2010 would that still be acceptable etc?

you can apply any time you want after you have been a permanent resident for 3 years.....

there is no time limit....

Thanks for that Marilyn.

As long as you still meet the requirements when you apply, you're good. All of the periods of residence and such are minimum requirements; there are no maximums.

But your actions can cause you to lose the right to file. Hypothetically, suppose you lived continously in the US for five years, and were eligible for naturalization, but didn't file. If you then left the US for a period of 6 or more months, you'd reset the clock on your continuous residence requirement, and be ineligible for citizenship until you accumulated another three (or five, if not married to a USC) years of continous residence. It doesn't matter than you had been eligible in the past; what matters is whether you have the required period of continous residence immediately preceeding the date on which you file and/or the date on which you gain citizenship.