Is a dog license purchased in one state valid in another? 
Specifically, my dog is licensed by Geauga County in Ohio.  She is
temporarily staying with me in Monroe County, Indiana.  Are her
Ohio-issued tags valid in Indiana, or must I pay another fee for a
license from Monroe County?  I know that other licenses, such as
drivers licenses and marriage licenses are recognized across state
lines as required by federal law.  Does this same law apply to dog
registration?  If not, are there any exceptions?  If dog licenses
aren't valid across state or county lines and you take your dog on a
cross-country trip, must you stop in each county and register your
dog?

I know this question seems frivolous, but a gentleman whose attempts
at a normal social life have obviously failed has decided to take it
upon himself to harass dog owners at the local dog park.  I want to
ensure that my situation is entirely legal before I involve law
enforcment and attempt to bring criminal harrassment and stalking
charges against him.

http://www.co.monroe.in.us/legal/countycode/440.htm

"Harboring"means the actions of any person that permit any animal
habitually to remain at large or to be fed within his home, enclosure,
yard or place of business or on any premises where such person resides
or that he controls. An animal shall be fed within his home,
enclosure, yard or place of business or on any premises where presumed
to be harbored if it is fed or sheltered for three (3) consecutive
days.

 440-21. Licensing--Requirement, Application, Fees, License Period,
Penalty for Violation

(A) Any person owning, harboring or keeping a dog over the age of six
(6) months must obtain a County license for the dog, except for dogs
in commercial kennels for breeding, boarding or training purposes.
This requirement shall apply to dogs owned, harbored or kept within
Monroe County, but shall not include those dogs owned, harbored or
kept within the City of Bloomington.

Is this of any Help?