Here are some of the themes I've used and liked! Some are premium some not but all good in my book. Artsee, Nova (elegant), In Style, Prestege 1.3, Yoo Explorer, gluttony. Not in any particular order. Hope this helps!!!
I'm using Thesis 1.8. Love it. Very flexible. Can customize theme almost any way. Skins, too. Great theme. $79. Good luck.
If you have less budget, you can start with elegentthemes, there is no price per theme, you can get all their themes by joining as a member.
Thesis is excellent for serious internet marketers who have learned that a simple, classic style works better than flashy, gimmicky sites. For them it is worth the investment in both time to learn as well as the money to purchase it.
Thesis seems to be the winner. Lots of good themes, but Thesis seems to be the best. And it's probably time to sign up before they come out with Thesis 2.0 and raise the price.
They look very classy, are fairly easy to manipulate, and you get good value for your $39 annual subscription.
If you're serious about Internet Marketing, Thesis can be a good investment. But it is a professional tool, and not for newbies.
I like themes from ThemeFuse. They provide original wordpress themes that are some of the best in the industry. They also update their themes to the latest version, hack proof and also provide good support. I have written ThemeFuse Review. You can check it out.
i suggest first you try out free ones, then go for paid ones. from what i have seen, there are plenty of free news themes which are as good as paid ones. i myself own http://top-best-themes.com for worpdress, vbulletin and joomla. check it out you make like my collection.
I have also bought Genesis all themes with developer license last month and I am liking it too. I personally like Genesis themes for the page load speed and SEO , Elegant Themes for design, looks and variety and Theme Junkie for simplicity, SEO and page load. I have developer license for all themes in these three providers and I as well as my clients are loving it. Hope to purchase Thesis Developer License too soon and would need to compare. The only drawback of thesis is that instead of one time or yearly developer license fee I would need to purchase license for each and every client website though at a relatively cheaper price than a standard member.