To modify the number of results returned ( note this is for the new v0.9 REST endpoints)
http://wiki.developer.myspace.com/index.php?title=Category:OpenSocial_v0.9_REST_Resources
Look at "Notes on query parameters" There are two parameters you'll be interested in (startIndex & count).
There are several updated SDKs for the new v0.9 REST endpoints which you can find here; They will make your life much easier in getting up and running. They also include several examples.
http://wiki.developer.myspace.com/index.php?title=OpenSocial_Client_Libraries
Thanks,
Jesse