There will be a few more posts with links to other electronics stuff whenever I get to doing that.

Buy parts online or at a local electronics parts supplier at your home town.

Look around for the lowest prices first, before you buy anything anywhere.

Also ICs and transistors have cheaper substitutes that will work just the same as the "Original" parts, look for cheaper brands and or "Generic" parts that will do the same thing(s).

Buy a semiconductor substitution cross reference guide book somewhere:

http://www.moyerelectronics.com/index.shtml?http://www.moyerelectronics.com/FreeDownLoads/

The famous transistor cross reference book is the Philip ECG semiconductor master replacement guide.

http://www.alibris.com/booksearch.detail?S=R&bid=7066821767&cm_mmc=shopcompare-_-base-_-nonisbn-_-na

http://www.ceitron.com/tech/specbook.html

http://www.elexp.com/bok_semi.htm

http://www.amazon.ca/Semiconductor-Cross-Reference-Howard-Company/dp/0790610507

------------A Short List, to find more of them use Google or other search engine:

http://www.intertexelectronics.com/
http://www.fairradio.com/catalog.php
http://www.oselectronics.com/

http://www.electronicsportal.net/s/transistor_referencehttp://focus.ti.com/pdfs/logic/xref_ti-national.pdf

http://www.ultimateusa.biz/?kw=semiconductors&gclid=CJTKx_fiwZECFQ8nawodbgvvDA
http://www.eciqrp.org/articles/fivebucks.html
http://www.electronics123.com/s.nl/it.A/id.1742/.f
http://www.electronics123.com/s.nl/it.A/id.311/.f
http://www.electronics123.com/s.nl/it.A/id.2218/.f?sc=8&category=33
http://www.electronics123.com/s.nl/it.A/id.472/.f?sc=8&category=33
http://www.futurlec.com/Components.shtml
http://www.elektronik-kompendium.de/sites/bau/index.htm
http://www.ak-modul-bus.de/cgi-bin/iboshop.cgi?placecart280!0,0,VCAP:1,0,1201523965640
http://www.partsexpress.com/electronic-parts.cfm
http://www.electronicplus.com/content/Alpha_C.asp
http://paja-trb.unas.cz/elektronika/navody/zapojeni_tranzistoru.html
http://www.valley-electronics.co.uk/index.php
http://www.electronicprojectsonline.co.uk/categories.php?cat=50
http://www.talkingelectronics.com/te_interactive_index.html
http://books.google.com/books?id=hSkgkWoCTOcC&pg=PA698&lpg=PA698&dq=astable+square+wave+oscillator&source=web&ots=6KmMYZGSJd&sig=UBELZLSFHZbp2pWrzXkJMkP_yPc
http://209.85.173.104/search?q=cache:5WG81vlOzEQJ:www.al7fs.us/Toner%2520Transfer%2520Presentation%252022Mar06.ppt+zapper+circuits&hl=en&ct=clnk&cd=38&gl=us
http://www.amazon.com/Giant-Book-Electronics-Projects/dp/0830613676
http://www.unicornelex.com/subcategory.php?cat=E32L35&
http://www.ace4parts.com/Default.aspx
http://www.mcminone.com/product.asp?catalog_name=MCMProducts&product_id=106-006
http://www.hobbyprojects.com/index.html
http://www.cricklewoodelectronics.com/Cricklewood/product.php?productid=5861&cat=&page=1
http://www.electronicprojectsonline.co.uk/proddetail.php?prod=BC107B
http://littlediode.com/components/catalog/BC107B-Transistor-p-16681.html
http://www.radarinc.com/cgi-bin/wspl.sh/category
http://www.cpcares.com/
http://dkc1.digikey.com/us/en/pdf/Current.html
http://www.elexp.com/index.htm
http://www.eham.net/articles/5217
http://www.electro-tech-online.com/
http://www.mouser.com/
http://www.newark.com/jsp/home/homepage.jsp
http://www.jameco.com/webapp/wcs/stores/servlet/StoreCatalogDisplay?storeId=10001&catalogId=10001&langId=-1
http://www.action-electronics.com/sitemap.htm#Search
http://www.electronics-lab.com/projects/index.html
http://www.componentsuperstore.com/store/SearchResult.aspx?PartNumber=PN2222A-J05Z&SearchType=ByID&ManufacturerName=FAIRCHILD
http://www.maplin.co.uk/Sub_Category.aspx?Menu=-2&doy=search
http://www.crystalradio.net/beginners3/cap.shtml
http://www.kenselectronics.com/lists/kits.htm
http://www.rsrelectronics.com/am_datak.htm
http://www.elexp.com/pro-vise.htm
http://www.zen22142.zen.co.uk/Circuits/Misc/misc.html
http://www.banzaieffects.com/BC107B-pr-16549.html
http://www.the-hdb-store.com/servlet/the-97/P2C--PROFESSIONAL-SELF-dsh-IGNITING/Detail
http://www.tequipment.net/PanaViseCBHolders.asp
http://www.dxzone.com/catalog/Technical_Reference/QRP_Projects/
http://www.rpelectronics.com/Default.asp?Main=/English/OnlineCat.asp?Menu=/English/Content/Categories/CatM_84.asp%26Detail=/English/Content/Items/P2C.asp
http://www.stopfdacensorship.org/
http://www.allelectronics.com/cgi-bin/category/100/index.html
http://store.americanmicrosemiconductor.com/2n2222.html?gclid=CMeBpLfQhZECFR-XiQoda3QM-Q
https://www.tselectronic.com/cata_index.html?tse_Session=7a2480e424a7f45d1ade17a93baa24f7
http://www.electronickits.com/
http://www.angelfire.com/electronic2/index1/
http://www.radioshack.com/category/index.jsp?categoryId=2032230&cp=2032058