You can buy electric air compressors certified for breathing air, that will give you enough pressure to fill your tanks. They won't be as fast as a shop's compressors unless you spend a lot of money on one, but they will work. Just make sure you don't get a standard garage/shop compressor; they'll put oil in the air, which can be fatal under pressure.
Cool, thats good to know. thank you very much....
Unrelated to this, for divers that have boats... what do you do with them? we don't have tie ups in the middle of the lake like they do here in the Caribbean... Do you take a third person to watch the boat... (kinda boring for that person... maybe) or how do you anchor down the boat, say if its super deep..