Is there a way to buy this game new (digital or CD) or you can only find it used?

You can't really get hold of new copies anymore however I can give you a link where you can find it if you'd like to buy this game? https://www.amazon.co.uk/Colin-McRae-Rally-2-0-PC/dp/B000077W0C/ref=sr_1_2?crid=1KMUU7PD2IODI&dchild=1&keywords=colin+mcrae+rally+2.0&qid=1585760301&s=videogames&sprefix=colin+mc%2Cvideogames%2C181&sr=1-2