Toyota dealer
I found a web site where you can get a manual for free as long as you join. It is by toyota i got my manual from there.
https://auth2.toyota.com/owner/web/page/home
I was lokking for the fuse box and this has the whole manual. Hope it helps you!
I very much doubt you can buy that on it's own. It usually comes only with a balljoint.
Buy a grand prix
You can buy a new, book (paper) version directly from the Toyota website, but they are expensive. I don't know why they don't sell cheap electronic versions (are they really focused on profits from repair manuals??). I bought my repair manual used on eBay for a big discount over new so do some searching. Finally, its totally unauthorized, but if you really search, you can find an electroinc (PDF) version of the echo/yaris repair manual floating around for free on the internet. I believe its technically the 1998 Yaris manual, but its pretty much identical to the 2000-2002 Echo manual although its missing some portions of the real manual.
Shop manual or owners manual? You can find both though the dealership, though toyotas website, and often on eBay. You can also find the shop manual online in PDF format from various "unauthorized" locations (google it).
As far as I know the only thing adjustable on the rack and pinion on the Toyota Echo is the toe. If you have the car aligned the mechanic will adjust it to within specifications for you. Other than that you would need some very expensive equipment that only shops and schools buy.
You can get a refurbished one for about $70. See: http://lmgtfy.com/?q=toyota+echo+mass+airflow+sensor
A used Toyota Echo can be easily found at any reputable used car dealerships. Additionally, online websites such as AutoTrader and Motor Trend carry used Echos for sale.
Buy the belt and get instructions from the place of purchase which they should have or check for a sticker on the top of the radiator cross member or on the under side of the hood
Buy a Haynes shop manual for 1997-2001 Toyota Camrys. They're about $15.
Probably one of the top 5 "best bang for the buck" cars you could buy in my opinion. Can get almost 40MPGs, very reliable, timing chain (not a belt) which is nice (no replacement schedule, can last almost forever).
buy the service manual
No you don't, regular is just fine.