good, i'm web designer too, but it isnt the wbdesigner's job to market the site
anyway, to clear you out, yahoo and google are different, its OK to say tht google is seach engine, but to say that yahoo is as well, its not, Yahoo is a directory.
search engine works with BOTS/SPIDERS, agents that fetch and catagorize every new site that uploads on web, so this fethching depends on how your META tags are defined specially keywords, and descriprion. submitting your site to google directly wont bring any help, you wont be listed on top after submitting, but you can be listed on top, a if you have effective meta tags defined, even you didnt submitted your site. google actually seaches for words in every page of the document and show these results (unless of course u arent paying for the search results on top)
you can submit in yahoo manually, and they'll catagorize your site accordingly. as its directory.