Webber286 is right on about the Sandbox penalty you are experiencing. It usually takes 3 – 9 months to get out, in which case it’s a good idea to use your time wisely and begin building links. You can also concentrate on listings on other search engines like Yahoo, MSN or targeted directories if your keywords are good sources of traffic from those places.
You should continue to build content pages. Keep adding articles on your main keyword subjects using unique descriptive titles for each article.
You currently have around 43 pages listed in Google:
http://www.google.com/search?hl=en&lr=&q=site:www.gamblingsafety.com
You could bulk that up to about 100 really good content pages and the results would be better for you. Then keep adding content often and make sure to update your homepage.
It’s good you have a site map, but you should list all the pages on the site that you want crawled and use descriptions of each page and link anchor text. You could try submitting a site map to Google site maps if you wanted.
While you are in the Sandbox start building links to your site. Google shows NO links for you right now, and you should try to acquire as many as possible from other sites related to yours. I know it’s hard to do for gambling / affiliate sites, but there are places to get links and linkbait ideas you can use.
Keep adding pages with unique titles, try to keep pages small in file size and under 100 links per page. You could consider adding in RSS or a blog to your site for faster results in Google.
Make sure every page links back to your homepage. I looked for a link back to the home, but didn’t see any on the sub-pages. You may consider adding in hypertext links at the bottom of each page using your keywords in the anchor text of each link.
Webber286 is mostly right about the domain name also. It is highly unlikely that is the reason for lack of rankings or slow start in Google SERP’s. It is one of many factors used to judge importance or popularity of a site in order to show up within page one results.