1.Submitting into search engines is of no use. The search engines will find you. Just leave enough links for them.
2. Submitting into directories helps. The problem is that you should do it manually and it is difficult to get listed with importnat directories, unless you pay.
Automatic submission will not bring any positive effect since most of submissions is into the link farms. There is speculation that being linked from such sites may get you penalty even if you do not link back. Thus zero effect is the best result you can get.
3. You can buy ranking with some completely useless SE, but not with the big players like Google or Yahoo. But you can buy advertisement with Google and your banner will be visible sideways of the natural results.
4. The only way how to ensure good placement in organic SE result is to pay a SEO firm or SEO your site by yourself.
5. This is webhosting forum and I therefore expect that your site is about webhosting as well. We do SEO, but I would classify optimisation for "webhosting" as extremely challenging and probably outside our current capacity. You need a lot of resources and manpower on terms like this one. On such big term, you need to pick up the largest SEO firm willing to give you a complete money back guarantee and get tens of thousands bucks ready.