Who said display:none is bad for SEO? That sounds like a myth to me. There are lots of legitimate reasons for using display:none and as always it's not the technique but the intent. Using display:none for style purposes is perfectly fine.
As mentioned by Pumbaa80 you'll almost certainly want to take advantage of JavaScript for this. Have all of the tabs available using regular links (reload the page to show the proper tab). This allows users who don't have JavaScript turned on to view the content. Then use JavaScript to hide the tabs except for the default one when the page loads. JavaScript will also be used to show and hide tabs as the user clicks on a tab and cancel the page load when they click on the link. This is 100% search engine and user friendly.
You can see this in action here. If you click on the tabs you'll see the page never reloads but the content changes when each tab is selected. If you turn off JavaScript the page does reload but the exact same content is available. A little less flashy then before but it's still accessible.
display:none, but Google might ignore hidden content (i.e. if the user can't see it, then it shouldn't be used for ranking). Also, most screen readers and text-only browsers don't read/displaydisplay:nonetext. – Lèse majesté Nov 15 '10 at 15:19