You mean Verizon.net email that you have from Verizon Communications DSL/Cable/FiOS service? You can use it on your Blackberry, but you're still going to need the $29.99 data plan.
You can have the Verizon.net email plus 9 other personal email accounts plus the @vzw.blackberry.net email. That's a total of 11 email accounts.
If I upgrade to a premium plan will that get me the same as the data plan?
Can I just connect a phone with email capability, not a blackberry to my verizon.net email?
Yeah, if you didn't want the full fledged Blackberry experience you can get a feature phone that's capable of Mobile Email. Most current feature phones are. You wouldn't need to get the Premium plan unless you wanted VZ Navigator too. If you don't want VZ Nav then you're better off paying $10 less for the Connect plan that will give you unlimited messaging, unlimited data access and the Mobile Email subscription.