I need to set up a dns record so that when the word shop is typed into a browser, it goes to the address 10.10.1.23/ecommerce. I know how to create a host record, but the /ecommerce part throws me off. Any help would be appreciated.

you can't solve that via DNS an option might be to create a IIS Website for the shop alias and do the forwarding to the 10.10.1.23/ecommerce from there (HTTP Redirection, see http://technet.microsoft.com/en-us/library/cc732969(WS.10).aspx , also make sure to have the option installed, tis not there by default)