Where is the county seat of lehigh county? Lehigh County. The City of Allentown lies within the County of Lehigh, Pennsylvania. The County Seat is located in Allentown, at Seventh & Hamilton streets. To gain information, or to search for a specific department or person, please visit the Lehigh County website.Where is the lehigh county assistance office located? The Lehigh County Assistance Office, offers assistance programs to inpiduals and families in need. Address 140 nth 7th st #1 555 Union Boulevard Suite 3Where is the lehigh county courthouse in allentown? Lehigh County Courthouse 455 West Hamilton Street Allentown, PA 18101-1614 Visiting the Courthouse in PersonWhat is the new website for the lehigh county tax claim bureau? Elite Revenue Solutions would like to welcome you to the Lehigh County Tax Claim Bureau’s new website: lehighcountytaxclaim.com. As agent for the Lehigh County Tax Claim Bureau, our goal is to offer the citizens of Lehigh County the highest level of service with easy access to public information.