After buying the Project Arcade book I went out shopping and found out how much on avg it would cost for items. Let's just say that the parts are NOT cheap and if you don't have a monitor/TV and computer you are looking at some $$$ if you want A-Grade parts.
here is my spreadsheet (hopefully it will take!) of what I found and where:
Supplies
Name Quantity Cost Total Link
Clear coat poly acrylic paint 1 30 30 Home depot/Lowes
Gallon of Black paint 2 15 30 Home depot/Lowes
Galon of Primer 1 15.97 15.97 Home depot/Lowes
3/4" inch MDF 3 18.85 56.55 Home depot/Lowes
5/8" 18"x 35" hardwood for CP top 1 15 15

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Screws (various sizes) 1 9.99 9.99 Home depot/Lowes
2 1/2" L-Bracket 6 2.82 16.92 http://www.lowes.com/lkn?action=productDetail&productId=45685-53911-ZAB205
2" L-Bracket 4 2.82 11.28 http://www.lowes.com/lkn?action=productDetail&productId=45685-53911-ZAB205
Shelf Brackets (9") 4 3 12
Cabinet Hinges 2 6 12
Surface bolt for Cabinet hinge 1 5 5
Velcro roll 1 2 2
Grommet Sleves 2 " 1 1 1 Hardware store
Glue sticks 1 2.99
Wod Putty 1 5.99
Sand paper 1 5 5 Home depot/Lowes
Caster (3") 1 15 15 set
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=26222&item=3813810127&rd=1Wood glue 1 2.99 2.99 Home depot/Lowes
Plexiglass sheet 1 $15 15 various sites
T-Molding (black) 60 $0 16.2 http://www.t-molding.com/cart/customer/product.php?productid=3&cat=16&page=1
Subtotal 280.88
Control Panel
Name Quantity Cost Total Link
3" Trackball 1 96.4 96.4 http://www.happcontrols.com/wp/item_search.html?item-no=56-0100-10
3" Trackball mounting plate 1 11 11 http://www.happcontrols.com/wp/item_search.html?item-no=55-1101-00
Horizontal Microswitch 25 1.85 46.25 http://www.happcontrols.com/wp/item_search.html?item-no=58-9100-L
1 Player Microswitch 1 1.95 1.95 http://www.happcontrols.com/wp/item_search.html?item-no=58-9111-L1PLY
2 Player Microswitch 1 1.95 1.95 http://www.happcontrols.com/wp/item_search.html?item-no=58-9111-L2PLY
Pushbutton Wrench 1 2.4 2.4 http://www.happcontrols.com/wp/item_search.html?item-no=53-8002-00
J-Stik Bal Top 2 14 28 http://www.ultimarc.com/controls.html
4-way Joystick 1 13.95 13.95 http://www.happcontrols.com/wp/item_search.html?item-no=50-7604-10
SlikStik Tornado Spinner 1 89.95 89.95 http://www.slikstik.com/SearchResult.aspx?CategoryID=4
18 AWG wire 45' spool1 1 5.49 5.49 http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=278-1223
22 AWG wire 45' spool 1 5.49 5.49 http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=278-1221
Quick disconnects-Blade 3 1.65 4.95 http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=64-3132
Spade Terminal (16 pack) 2 1.69 3.38 http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=64-3124
I-PAC4 PS/2 1 65 65 http://www.ultimarc.com/ipac1.html
Optic-PAC USB 1 44 44 http://www.ultimarc.com/optipac1.html
Opti-PAC Spare Cables 1 9 9 http://www.ultimarc.com/optipac1.html
Subtotal 429.16
Misc
Name Quantity Cost Total Link
MAME Roms 1 30 30 http://www.freemameroms.com/
24" TV w/S-Video 1 144.49 144.49 http://www.bestbuy.com/site/olspage.jsp?id=1051806303676&skuId=5336237&productCategoryId=cat03003&type=product
Athlon 2600+ computer 1 413 413 http://www.tcwo.com/cgi-bin/webc.cgi/st_prod.html?p_prodid=1504&sid=44oBmP0-IMSp7Rn
Radeon 9600Pro w/S-Video 1 135 135 http://www.tcwo.com/cgi-bin/webc.cgi/st_prod.html?p_prodid=740308&sid=44oBmP0-IMSp7Rn
Subtotal 722.49
GRAND TOTAL 1432.53
This is not including the tools it would take to build the thing, that alone is another $600 at least for a table saw, jig saw, and other equipment. Best to rely on your friends for that!