BBC Sound Effects is one of my favourite websites.

The website says:
These 16,000 BBC Sound Effects are made available by the BBC in WAV format to download for use under the terms of the RemArc Licence. The Sound Effects are BBC copyright, but they may be used for personal, educational or research purposes, as detailed in the license.
For commercial use, you can license sound effects.
Just to whet your appetite, these are a few of the samples from the site that I really liked.
BBC Sound Effects : Waterfalls
You can enjoy the powerfull and soothing sound of surging water.
BBC Sound Effects : Birds & Backgrounds
A variety of delightful birdsongs.
The website mentioned Pro Sound Effects Online Library site here.

Category : Birds – Land
Description: American Bald Eagle. Mc Alarm Calls, Wind In Trees. St Lazaria, Alaska
Description:American Redstart. CU Song, Rufous-Sided Towhees And Other Birds In Distance, Stream Or Wind In Trees In Distance. Bent Creek, Blue Ridge Mts., N.Carolina, U.S.A
Category : Insects – Land
A glimpse of the hidden world of insects, drawing in the listener by its variety of interesting sounds. Become privy to unique sounds that we cannot hear clearly in daily life.
Description:Beetle. Large Species (Possibly Longicorn) Stridulating And Scraping North Borneo
Description:Bog Bush Cricket. Male Stridulating Dorset, U.K
I could finally identify the interesting sound at the rocky beachside where my family heard this insect for the first time.
Last but not least, the famous musicians of the insect kingdom, crickets.
Description: Crickets. Stridulation, With Tree Frogs Bermuda
Description: Cricket Sp. MCU Stridulating In Bushes. Other Crickets In B/G. Foraging Sounds From Birds In Bushes. Chincoteague, Virginia, U.S.A
Description: Cricket Sp. CU Song. Other Crickets In B/G. Sauheber Wildlife Sanctuary, Henderson, U.S.A
What kind of sounds from your daily life or memory, would you like to pick out and discover?