Here is the list of most of my suppliers, lately I stick with Future.

Note however that there may be a 40-200% price difference for some things

Like 74hc283 4-bit adders are 2500 minimum order at digikey but future allowed me to order 25

Future once had the XMOS processor boards at $65 but they were $100 from digikey

Digikey lists parallax boards at $50 but they were $25 at parallax.

Sparkfun seems to have consistent prices.

Adafruit

To lay out breadboards you can experiment with

Future Electronics – montreal – future is the best with no import duties – this is where I got all my raspberry pis and most of my 74hc chips

Active Components – good for breadboards, wiring and power supplies/meters but I don’t buy components there anymore

Active Tech, 1465 Merivale Rd, Ottawa, ON K2E 5N9, Canada

All the following may have shipping and/or import duties from 20-40% + exchange

I have ordered from all of them over the years

Sparkfun NY – all components

EvilMadScience CA – mostly for LED projects and DIY projects –husband and life team

You can order their cat

Parallax

Parallax CA – parts around robots and their 8-core microcontroller

I have most of their custom controllers and a lot of their propeller boards

XMOS

Makers of the replacement of the transputer board – 32 thread – 4 core microcontrollers

digikey – I might have ordered once from them but Future above covers them off

MountainKingTech – I ordered enclosures and a 100’s lot of angle brackets and bolts for connecting boards together