Nice Idea for sewing desk. Make the table Counter height and possibly a bit wider. Use the extra shelf space gained from the additional height to store the sewing machine when not in use. If possible make dimensions so that the shelf base can be turned either way depending on situation of table.
Aubrey & Lindsay's Beautiful DIY Basement Studio Desk
Per poster: used ClosetMaid storage items from Target. I have a small bookshelf, four drawers and cupboard and we painted a 2'x6' peice of plywood for the top. The whole project cost about $75 and took one afternoon including the shopping! The ClosetMaid system made a counter height desk so I sit on a stool but I use my desk for scrapbooking and end up standing most of the time anyway.