A good text is the 2e Forgotten Realms sourcebook Faiths and Avatars (F&A) that provides generic information about deities. For each power level, the following information is provided:
- Shapeshifting: for example, greater powers are known to assume forms of planetary sizes.
- Magic resistance: against spells of mortals, and other powers
- Saving throws: whether they automatically succeed, etc.
- Planar travel: teleport, travel between planes, etc.
- Sensing ability: how "omniscient" they are.
- Creation: how "omnipotent" they are, and how long they need to rest after creating various things.
- Life and death: whom they can kill and to whom they can bestow life with a thought.
- Multitasks: how many separate things they can do at a time.
- Avatars: how many avatars they can employ simultaneously.
- Immunities: need for magic weapons to harm them, immunity to save or die spells, etc.
Beyond these generic data, the book refrains from statting deities individually, while a lot of data are provided for the avatars. It mentions that the avatars embody "a small portion of the god's power", and "an almost infinitely vast gulf of power lies between the god and the avatar". Note that 2e avatars are already very powerful (some more powerful than the 1e powers themselves), so trying to stat deities is not going to be very meaningful.
Note: All the information from F&A that is listed above is also present in the 2e version of Legends and Lore (L&L 2e), published in 1990. Assuming that one of the goals of looking for the gaming statistics for deities is to make them targets of player characters, you might be interested in knowing that the L&L 2e explicitly mentions that:
... gods ... cannot be killed by anything save another god of greater stature, or by a god of any stature using an artifact. This means that no mortal may ever kill any god.