AZ Marijuana Charge

What is the name of your state (only U.S. law)? Arizona

I was arrested in 2003 for possession of Marijuana in Tempe. I was there for work and shortly after my arrest moved back to my home state. I will be returning to work in Arizona this winter and I know that I have a warrant. I am willing to take care of the case and was wondering about details. If the arresting officer is no longer working for the Tempe police do they still have a case? Would it be dropped like a traffic violation when the officer doesn't appear?

Even if the cop isn't employed anymore, they can subpoena him as a witness.
No doubt there is a bench warrant for the failure to appear. You can try calling the court, but a lawyer might be your best bet to grease things along at the minimum of grief (and period of lockup).

If you show up to the court (with money!) and turn yourself in, this is typically an easy process.

As for the drug charges, that will also likely be easily handled.

Since you are looking at charges that could include jail time, FR's advice of finding a lawyer is certainly a good one. You're probably gonna want the lawyer whose office is across the street from the courthouse. Yes, they will be expensive, but consider it an investment to keep yourself out of jail. A local attorney knows best what the courts want to hear, and as such present the highest potential in yielding the most favorable results. Many attorneys will offer free/cheap consultations, so you may wish to take advantage of this and sit down with a couple to see what insight they have to offer.

My guess is you should be able to get through this alright without an attorney, but, were I in your position, I really wouldn't take that chance. If you need to borrow money from a friend/family member to retain that attorney, then I recommend it (after all, hard to get paid for your new job if you can't show up to work due to be jailed).