You say "pay stubs" instead of W-2. You can still get copies of your W-2s. See:
https://ttlc.intuit.com/community/taxes/discussion/how-do-i-get-my-old-w2s/01/782516#M311511
If you were not a regular W-2 employee but were some kind of contract employee, you are considered to be self employed. You would file taxes based on your own financial records. Some of the companies/people you worked for may may have filed form 1099-Misc on your payments, if the individual amount was more than $600. You can expect to pay about 14% as self employment (social security and medicare) tax., in addition to any income tax. Or, you can expect any refund to be reduced by self employment tax.
