Is there a deadline as to when you should receive a 1090 tax form showing taxable earnings?

There is no IRS Form 1090. Form 1099-MISC is Miscellaneous Income. When the Payer (person/business who paid you) sends you a Form 1099-MISC, they consider you as self-employed. That's why they're sending you a Form 1099-MISC, not a Form W-2 (Wage and Tax Statement).

Generally, payers and employers are required to provide/send 1099 forms and W-2 forms by January 31st. If January 31st falls on a weekend, the deadline is extended to the next business day. Form 1099 and Form W-2 are due by February 2, 2009 for 2008 income. They're due by February 1, 2010 for 2009 income.