Check out the combo boxe's LimitToList property in Access Help.
Have fun with the web stuff. I've enjoyed messing around with the ASP.NET Starter Kits and MS's TaskVision XML web service demo app on local IIS and SQL Server installations. Been reading Dino Esposito's "Programming Microsoft ASP.NET" for about three years now. Think I'm on about page 200 or so. So many toys, so little time. :(