There is a wealth of information at Hifi-remote.com, with about 3500 "upgrade" files.  There is a lot of info here too, but it is typically in Pronto Hex format, or its derivitives, and it takes some expertise to convert these. 

There are software tools which are intended to allow you to customize the behavior of the remote by connecting it to a PC via the JP1 connector inside the battery compartment. One of the tools, called RemoteMaster, will also tell you which EFC to use in manually programming the remote, assuming your component or a similar model is in the Files Section. So you would download and install RM, along with files which describe the internal workings of the remote (RDF filles) and images/maps of the remote. (If you have a JP1 cable, you can use the image of the remote to assign functions to a particular key by drag and drop.) Then you would look in the File Section, Upgrades, and find one or more upgrades which may be similar to your component.  After downloading the upgrade and opening it in RM, the EFCs are shown. If you want to try this, please read the sticky in the Beginners Forum entitled Read this First.

RM is aimed at people with cables, so you'll just be piggybacking.  It does mean that quite a bit of the program has no value in manual programming.

Another source of EFCs is the Lookup Tool.  It mostly shows the EFCs that are built into various UEI remotes.  For manual programming, teh Lookup Tool is very useful in finding a setup code which uses the same protocol executor as the upgrade.  In most cases, it is necessary to find a setup code which shoots the same device numbers, although Sony and JVC can use Combo protocols which tend to be able to shoot any device number.