Hi Mate,
Best place to start is reading forums like seochat.com about what is required. Keyword placement and density is very imporant. Spiders crawl pages which are publically available, eg. they exist on pages which doesnt require login.
A couple of quick pointers:-
1. Keep your keyword density (ie. keywords you want Google to rank you for) below 5 or 6% per page. DO NOT keyword spam (ie. put thousands of clustered keywords together)
2. Google rank your page on relevant backlinks, make sure required keywords are in the Alin URL, this mean on the pages that link back to your website, they link contain key phrases (eg. top 20 games), and then link to your page
3. Domain name is VERY important. With a keyword domain you are likely to rank quicker since your content is relevant.
4. Get a sitemap on your homepage. This will make it easier for the spiders to index other pages as well.
5. Do NOT use submitter services, in fact, do not submit your site to google and yahoo. I found by creating backlinks from relevant sites and blogs indexed my websites in substantially less time.
Some people out there will say get your meta tags in order, but to be honest, after experimenting with meta tags on 7 of my websites over a period of one year, the only difference they made was on MSN, the big ones (ie.Google and Yahoo) didnt seem to care otherwise. They are more concerned about visible content, which is what it should be.
This is just the highlights. Remember that the rules changes frequently, and the search engines are tightlipped about what the actual algorythm does to prevent spammers and scammers rank their sites using black hat methods.
Another point, webdevs URLs arent really spider friendly, but it wont stop yahoo and google, since they are pretty advanced.