Glad to see you managed to survive Han Solo's scary piloting you down to Mos Eisley, he might be grumpy at times, nothing to worry about.
OK, resources. Everywhere I would say.
However, I interpret your question that you never found your way to Beginners Guide for Traders
. Not only is it a good starting point for any crafter but it is good to know that "this subject, what was it now..." and easily find it again.
To be frank, your question is answered to in the first few chapters more than one time.
To be frank again, Traders is one of those professions where a little reading takes you from novice to top-notch Master. If you refuse to read or skim through a guide you will just level up to master, but no more
I hope you followed the advice and got yourself the pistol from the Imp/Rebel quest, did you??? For meat and hide, take it with you and just walk outside Mos Eisley, you will see herds of animals. Focus on just one kind because they have different kinds of meat and hide which makes it harder for you to get the amounts you need. Be careful, some of them do not like that you kill its mate, and Traders are not too good to survive a massive attack.
How much meat and hide do you need? It is also in the guide