Infopath Form Services - SharePoint Custom Lists

http://blogs.msdn.com/b/infopath/archive/2007/03/26/submitting-to-a-sharepoint-list.aspx

http://msdn.microsoft.com/en-us/library/cc162745(office.12).aspx#ip2007SubmitDataSPList_CleaningUptheLayoutoftheForm

http://blog.completesharepoint.net/post/2009/08/16/Integrating-Custom-ASPNET-ASPX-form-into-Sharepoint-InfoPath-Form-Service-Programmatically.aspx