I've put together a short article with screen shots on resolving right-alignment issues with labels.  The solutions are simple and obvious, once you know to look for them:

1. Make sure the html element used for labels (span in this case) is large enought to handle different font settings.
2. Be aware that the font you are using in the Visual Studio 2008 designer is probably not the same for most of your users.
3. If layout is critical, you should probably specify font-family and font-size in the element's style. (However, be aware the user can override your settings.)
4. Always test your web page with an accessible theme in IE or FireFox.

I used to purchase most of my technical literature from a web site called bookpool.com.  It was an excellent site for purchasing technical books.  Alas, today, I went to the site, determined that I would "catch up" on .NET 3.5 literature and get a head start on .Net 4.0.  But the site is gone!  (It's a GoDaddy unclaimed site now - not even a picture of Danica on the page to cheer me up.)  I did a quick search and found a lot of chatter in the April time frame that the site was down and it appeared the company had gone belly up.  I guess this is just another casualty of the recession.

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Sorry for the Google advertisements.  Economy is lousy, I need the money.  Please click.

The ads are terrible.  I know it, you know it.  All I can say is sorry for the cruddy google ads.