Hi, it is possible to regain German citizenship.

See § 13 StAG.

http://www.gesetze-im-internet.de/rustag/__13.html

You can ask for it at the German embassy, too. You should declare that you are planning to go back to Germany and would leave U.S. citizenship. This would make things easier.

This is the form you will have to fill out:

http://www.bva.bund.de/cln_092/nn_385390/DE/Aufgaben/Abt__III/Staatsangehoerigkeit/Einbuergerung/Ermessenseinbuergerung/AntraegeMerkblaetter/Ermess__Antrag1P,templateId=raw,property=publicationFile.pdf/Ermess_Antrag1P.pdf

The process will need several months up to a year, because it is a so called "Ermessenseinbürgerung".

The authorities have dicretion to decide whether to give you the German citizenship. So they may collect a lot of extra data about your life and economic background. This all takes time.

You should state your connections to family in Germany, that you are able to maintain yourself or who will maintain you.

The issue of medical insurance should be resolved...

In your case I think it will probably be possible to regain the citizenship, but it will take its time.

It is possible to get a residence permit (Aufenthaltserlaubnis) and this gives you the right to work in Germany, see § 38 II AufenthG.

However, the authority can decide whether to give it to you. You should especially prove your German skills and economic background.

See also § 5 AufenthG.

As a US citizen you do not necessarily do the paper work via the German embassy in the States (although recommended). can also enter as a tourist to Germany and ask for the permit at the local Ausländerbehörde at your place of residence.

http://www.gesetze-im-internet.de/aufenthg_2004/__38.html

http://www.gesetze-im-internet.de/aufenthg_2004/__5.html

Not necessarily but may make things easier...