I was convicted of attempted forgery (a felony) in New Mexico.. Can i legally purchase and own a firearm?

No.

Do I need a criminal defense attorney?

It's not a bad idea to retain an attorney to represent you to ensure you're doing everything you can to keep this off your record.

Does a criminal defense atty have any duty not to discuss a former client with prosecutor after the representation has ended?

Your attorney has a duty of loyalty as well as a duty of confidentiality. See www.calbar.ca.gov, specifically the California State Bar Rules of...

he didn't need probable cause to approach you. A passed out driver in a car may need help, may be dead or something like that. If you were, say...

In 1990 at age 25, my German nephew was federally indicted in US on 6 counts of possession and intent to distribute cocaine.

You need to hire an attorney familiar with federal cases. The feds don't like to dump cases because a defendant absconds and then merely waits it...

The court has ordered that i do 60 days worth of uas that should total 16 ua. I completed 17

you should discuss this directly with your lawyer.

They can do it, but what proof do they have? Make them sue you and prove it. Sounds ridiculous.

I don't practice in UT, but in many jurisdictions, they still charge DUI if they can show you were impaired. They need not prove you were .08 or over

Is my un-charged felony pot arrest slipping through the cracks?

Maybe they referred your case to the feds. . .

What issues in probate court, validity of a will, am I entitled to a Jury trial? some unique issues came up in discovery rspndnt

You've tagged this as "criminal defense" but you should put it down for "Probate" or "wills"