Some community flea markets or garage sales can be a good option. People come there looking for all kinds of used items, including books. Just set up a booth and see if you can make a sale.
Well, libraries in your area might have some comic books available for borrowing. Another option is to look for comic book specialty stores in your neighborhood. They usually have a wide range of titles.
Some thrift stores in your area might take comic book donations. It's a good way to give them a second life. Also, you could check with schools or youth organizations that have reading programs. They might be interested in adding comic books to their collections.
One option is to search online for professional comic book grading services that operate in your vicinity. Another possibility is to ask fellow comic book collectors in your local community groups or forums for recommendations on where to get comic books graded nearby.