Hi,
We will need some more information to understand your network. Where to is the E1 connected, what is the other end?
Which interface card do you have for terminating the E1?
What kind of E1 does the service provider give you (structured, unstructured, etc.) and what are the parameters (hdb3, crc4, etc.)?
In any case you could find something in either "T1 and E1 Controllers"
http://www.cisco.com/en/US/docs/ios/12_2/dial/configuration/guide/daficl.html#wp1001208
or maybe even at "Configuring Serial Interfaces"
http://www.cisco.com/en/US/docs/ios/12_4/interface/configuration/guide/icfserih.html
Those links will provide the information to configure the usual WAN solutions found around E1 interfaces. In case you can provide answers to the questions above, we could provide you with a sample configuration.
Hope this helps! Please use the rating system.
Regards, Martin