You might find this thread interesting:
http://forums.ddo.com/showthread.php?t=289779
Max Int, SP, Spell Penetration and spell DC for Wizards
Don't expect to actually reach any of those numbers. It's just a list of what is theoretically possible. You should have mid-30's for most of your spell DCs as a Wizard when you hit level 20 and you should probably have a 39 or 40 DC in whatever specific spell school you choose as your specialty after you have acquired a bit of gear for your Wizard.
18 starting Int
+5 level ups
+6 item
+2 tome
+3 class enhancements
+1 exceptional stacking Int
+2 exceptional stacking Int
+2 Wizard capstone
Total "easy" Int = 39
Add +1 for an upgrade to a +3 Int tome
+2 Ship buffs
+2 for Yugoloth potion that lasts 15 minutes
Total reasonable Int for most quests and raids = 44
+2 Lich form
+2 Completionist
+1 for upgrade to a +7 Int item
+1 for upgrade to a +4 Int tome
Litany of the Damned trinket +1 profane bonus to all stats
Alchemical +2 Int from Lord of Blades/Master Artificer weapon
Total for complete DDO lunatics: 53
+1 more for Humans or +2 more for Drow