There's an Amazon Monopoly on electronic components and related stuff? Check out our curated list of suppliers on Reddit:
CPC Farnell UK
Electron Electronics UK
Element14 UK AKA Farnell.
Mallinson Electrical UK
Mega Electronics UK
Rapid Electronics UK
RS Components UK
Squirrel Labs UK
Arduino, components and robotics:
Cool Components Some say "The UK's Sparkfun".
Kitronik BBC micro:bit partner. Kits, Arduino, Sparkfun parts and components.
Oomlout Arduino, Adafruit, Sparkfun and components.
Pimoroni Stocks Adafruit parts.
Proto-PIC Stocks Adafruit and Sparkfun parts.
SK Pang Stocks Sparkfun parts.
ExpTech Boards and modules, robotics etc.
Tinkersoup Arduino, modules etc.
Waterott Electronic Boards, kits, robotics, components.
There's also a supplier in Thailand called Tayda that has stupidly-cheap stuff and 2 week delivery - they are used by many UK and global hobbyists.
Yes, Maplin is on our list - with a comment that they aint what they used to be in terms of stock and pricing. I could go on, but suffice to say I have a 4 digit Maplin customer number as one of their early accounts and the current company is not a patch on the 'original'. For others that hark back to the 1970s-80 hobby electronics scene and the Maplin catalogue, coloured vouchers you could collect towards future orders and the decent projects, check out some nostalgia here: