Re: Can anyone suggest a dojo in Maryland
I second Asim's recommendation of Capital Aikikai. Trained there as well and my experience was very positive.
Regarding spirituality of practice I think this is defined be each individual differently. So I think the best approach is to use the Aikiweb dojo search engine or google to make a list of dojos and then go visit practice sessions to get a more personal feel of how spiritual a dojo's practice may be.
Best to you.