It looks like you had a hard time on installing the OpenCart on your website. Anyway, it is a good thing to find a tutorial for setting it up. The work is quite easier after learning more about the basic installation.
Using a starter package on most web hosting could at least give you a good grip. I think I’ve read something about Vidahost already and they say it is really easy to setup and it is really affordable. Anyway, it is better if the upgrade is easy for just few clicks and done.