I've built about 8 mods, mostly DNA40's, 7 of which are still in the rotation. I started with a hammond with dual batteries with a DNA30. I would definately recommend building a hammond box to start with. I would not reccommend using any kind of glue to glue the board down. You may want to remove that board at some future date...I did.
As far as enclosures go, only your imagination is the limit. There are companies that provide 3-D printing services so if you can use CAD software and design your own enclosure they can print it for you. 5 of the mods I have were printed on a 3-D printer (someone elses design, 'cause I'm CAD illiterate). There are also a number of different board holders or screen bezels that can be printed to "class up" a hammond box. Shapeways.com is the site that first comes to mind.
Hardware, switches, fuses & other hardware come from either mcmaster-carr or mouser.