I tried a strategy once which is to sell cheap hosting for college students that needs hosting for their projects, they grow, and their needs grow with !

forums are the best.

Forums work great, but there are many other forms of advertising to try. PPC maybe be quite hard, but why not try local newspapers or community websites?

Blog and forum posting really works great!

Agree. The best thing is to diversify your advertisement and your presence.
But word to mouth is the best for long term customers

You are quite right.
But what you said can be put in those words: advertise to people that are likely to buy your product.
Interesting if you are a webmaster ... you all ready have a HOSTED site.

No its not only that way, There are several ways to advertise. community interaction, social media, and etc.

We prefer forums and banners.

Forum posting is great, but, it depends on the season, you have bad business seasons online too.

We do web master forums however we do use google adwords of and on.

google adwords and facebook ads is good also

I guarantee Forum is the best place to advertise your product.

I agree, anywhere and everywhere. Then advertise directly against your competitors. If they have potential clients looking at them, why not at least spark a little interest? After that, referrals, referrals, referrals. In all the sales organizations, we pushed that more than anything else, just like a real-estate agent, "I'm glad we found you a house, now if you know anyone else that is in the market please give them my card"

No,there must many good forums that help us to get customer on our website.

Happy customers talk to their friends and you get more sales.
This is the best advertising