We have a 33 gallon "gas" heated tank. Seems to run out of hot water after the first shower in the morning. Is there any maintence I can do even know I have no knowledge of hot water tanks or plumbing?

Well, yes you can. If it is just running out of HOT water after one single shower, the total hot water capacity is very small and/or the heating of new cold water entering the tank is not functioning optimal.
First of all clean the entire tank area. Where ever you have access, have a look and clean there too.
See (if that is possible) if the tank floor is covered with sand or dust (entering the tank together with the incoming water. That reduces over time the water quantity in the tank.
Also check the heating element : is it covered with scale? That reduces the transfer of heat into the water. Remove the scale. If impossible replace the heating element.
Contact me back if you keep having problems. May be your findings are a source for new suggestions!
Success!
;)

Gas water heaters DO NOT have heating elements. Best to call a service person for this. May just be that it needs to be flushed and adjusted.

First drain and flush the water heater. There is a drain at the bottom of the heater to which you connect a hose. Let water run until it is clear. Some times the sediment in the heater will make the valve leak after draining. If this occurs purchase a cap for it. If this does not solve the problem you may have a deteriorating dip tube. Come back and tell us how a long is a normal shower.