If you are in a tropical region, you may find them fresh at local farmers' markets:
Ice cream bean fruit ( Inga edulis ) is primarily available through specialty tropical fruit distributors online or at local markets in warm climates like South Florida and California. Because they are highly perishable, they are rarely found in standard grocery stores. Where to Buy Online
Several specialized fruit farms offer shipping across the United States. Many of these operate on a basis due to limited seasonal windows.
— A "must-try" for fans of unique textures. Go to product viewer dialog for this item. Ice Cream Bean
: Sells "sampler" packs (1–1.5 lbs) for around $74.99 and larger 5–6 lb boxes for $154.99.