one thats common and used by alot of folks, is Peters plant food, a higher first number is for veg growth, one with a higher middle number is usually for the bud cycle.

I forget all the kinds they make, I use 20-20-20 indoors, and add some extras to it.
I think they sell 20-10-10 and 15-30-15.

It not the very best fert,but it will do fine,thousands of plants have been grown with it,you should be able to find it at home stores, ace hardware, maybe wally world, the also have a website.

Its better to use ferts at half strength, than to use to much....