Another noteworthy resource is the HuGE Navigator GWAS Interagator. This is a search tool similar to the NHGRI GWAS catalog, but more focused on a search terms. Handy links are provided to other resources. Of particular interest are links to visualize the variants in the UCSC Browser.
I am sure other GWAS resources exist as well, but these were the two main ones that first came to mind for me. If you know other great GWAS resources capable of linking a genomic marker with a disease, please share in the comments below.