Microsoft Excel - EXCEL forms

Can anyone tell me of an application that can be used to easily make EXCEL user forms?  I have an EXCEL program that is used by almost 50 people.  Although it is a robust program that does a ton of caculations, it still has the plain old cell by cell, spreadsheet, data entry.  I would love forms that make it look and feel more like a professional application however, I do not know vba code or whatever is needed to create EXCEL forms.

Thanks

VBA UserForms would be the way to go. This articles explain building UserForms with examples -
http://www.exceltip.com/st/Create_User_Forms_in_Microsoft_Excel/629.html
http://pubs.logicalexpressions.com/pub0009/LPMArticle.asp?ID=362

Alternatively, you can build forms over the Web using Zoho or Google Docs & download the user entered data as a spreadsheet -
http://labnol.blogspot.com/2007/07/create-web-forms-with-zoho-creator.html
http://docs.google.com/support/bin/answer.py?hl=en&answer=87809

Excel has a simple data entry form capability that you might want to use.  Select any cell in the list and press Alt+D,O.