Effects Design Sites
There are many good engineers around who have helped with theory and ideas and have taken the time to share their experience. I can heartily recommend these sites:
R.G.Keen’s site, Geofex: http://www.geofex.com
Jack Orman’s site, AMZFX: http://www.muzique.com
John Hollis’ schematics page: http://www.hollis.co.uk/john/circuits.html
I’m based in the UK so I tend to use British suppliers. These are the ones I use the most:
Farnell Electronics: http://uk.farnell.com (minimum order value of £20)
Rapid Electronics: http://www.rapidonline.co.uk (now comparatively expensive on delivery)
Technobots: http://www.technobotsonline.com (they have low small-order charge)
Spiratronics: http://spiratronics.com/ (excellent service, low postage charge. eBay or their website)
Buying Stuff From Ebay/China
I have quite a lot of experience with eBay and I generally take the view that you will win some and lose some so I have been happy to risk buying direct from China/Hong Kong. I have to say that (on the whole) it’s been relatively painless. Shipment time can be a month or more – so you need to be patient.
Generally speaking, it is wise to only buy semiconductors from a reputable supplier as there are an increasing number of fakes around. Consequently (and regardless of any price disadvantage) I always buy semiconductors from reputable British suppliers if I can.
However, in the world of guitar effects there are a number of components which are obsolete and not generally available so you have to try potentially more risky suppliers.
At the time of writing (February 2012) I can recommend the following eBay sources:
Yoyo Components: http://stores.ebay.co.uk/Yoyo-Components-UK-Ltd (UK stock)
goodbuy7888: http://stores.ebay.co.uk/ledlightbulbworld (Hong Kong; successfully bought 1N34A and MN3007 and PT2399).