There are two seperate processes here
1. Uploading the file
I have found many code examples on the web and the best I have used can be found at:
http://www.lewismoten.com/CodeLibrary/Browse/ASP/[All]/1.htm
I used the first incarnation.
2. Send an email
A good script is at:
http://www.4guysfromrolla.com/webtech/112298-1.shtml
You can modify these to work together to produce the result you want.
Try them and then post any problems on this site.
Of course you can also buy a third party component as DaveGerard suggested however this is not too difficult to accomplish by yourself if you are trying to learn ASP.
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They say, best men are moulded out of faults,
And, for the most, become much more the better
For being a little bad.
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