Anesthetic options for lipoma on temple. Do I have the option to ask for general sedation?

That is a location where not only would you be more comfortable, but depending on the exact location there is a small nerve that traverses the area.  The surgeon would appreciate a still patient to dissect out the nerve.

This can easily be accomplished as an outpatient procedure with local anesthesia.  If you strongly prefer general anesthesia, check with your surgeon to see if he/she is amenable to doing the procedure this way.

I would normally remove a lipoma on the temple in the office with just local anesthesia.  I have never had a patient have a problem with this type of anesthesia for this procedure in the past.  Having a general anesthesia for this procedure is not necessary, and it would also substantially increase the cost.  Even when a general anesthesia is used for a surgical procedure, local anesthetic is normally used to help with pain and bleeding.  The amount of local anesthetic needed would be relatively small for this procedure.  

Many thanks of your question.
Please feel reassured that is is a very simple and quick procedure to have done under local anaesthetic - I perform many of these on a regular basis and cannot ever remember a patient having a general anaesthetic for this - and that includes quite young children and adolescents.
General anaesthetic raises the risks of complications (from the anaesthetic) as well as costing significantly more, and in any case, local anaesthetic will be injected into the area for lipoma removal whilst you were under anaesthetic.
I wish you luck and recommend you seek the opinion and treatment from a Board Certified Plastic Surgeon.
Best of luck.
Marcus