Is there a way to find out which are new tokens which would be listed on Coinbase over a period of time?
Yes there is and that is by knowing insider knowledge from someone working at Coinbase,,, or if you happen to be in the inner circle of people who are negotiating to list on an exchange as big as Coinbase.
It is wrong and you can get fined or even jailed for insider trading. Ask Martha Stewart;) But I suppose 2 years in nice people jail is worth making millions.