Hi Josh,
You should have a copy of ArcPad Studio installed along with your copy of ArcPad 10.
If you open ArcPad Studio and open the .axf file that you have created during checkout, you will be able to edit the forms by expanding the 'Feature Layers' branch in the .axf and double clicking the selected feature layer. This will open another window for that feature layer that contains information such as symbology and forms. Expanding the 'Forms' branch will give you a list of all of the properties of the forms.
With this window selected, click on the 'Forms' button in the main toolbar that runs along the top of ArcPad Studio (it looks like two blue and white forms). This will open the 'Forms' editor. Choose which form you want to edit (EDIT or QUERY) or create a new form from here.
For more information, consult the ArcPad Studio Help.
Hope this helps!!
Hannah Ferrier
Mobile GIS Specialist, Maptel