Forms Data Controls :: Lighten Too Many GridViews In One Aspx Page

the project I'm working on has become quite bigger then expected. And now I have pages containing about ten different GridViews (and it is likely to increase!!), each one with its own EditItemTemplate, ItemTemplate, FooterTemplate, style, properties, etc. And, of course, in the code-behind (C#) each Grid has its events handled. You can imagine: it is a mess, playing with visibility of each one, ImageButtons to hide them, further buttons for other actions. I decided to handle only events in the code behind, while using partial classes and additional classes for the rest of the code (SQL queries and everything else), but still, it's gettin a mess.

Well, my question is: is there a way to, how can I say, have a kind of separate files, where these objects are deployed, and from where I can reference them when running the application. Or, if it exists, a way to lighten aspx page and asp.cs pages. I know it's part of the job, so here the question is just intended to investigate whether a possibility to "distribute" the objects used in a web page exists.