Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Gramado (38% of total searches to Rio Grande do Sul). The next most popular destinations are Porto Alegre (31%) and Pelotas (25%). Searches for hotels in Torres (6%) are also popular.
KAYAK users have found double rooms in Rio Grande do Sul for as cheap as $24 (Porto Alegre) in the last 3 days. The average price is $153.