Ok i got new after market rims for my 99 honda accord but they need new tires and the tires on them now say 205/40 R16 and im just wondering if 205/45 R16 tires will work cuz i cant find any others that are used and in good condition

 

They should be fine. Not a huge difference.

 

205/55-R16 would be an even better size, to match the outer tread diameter of the stock tires (195/65-R15 or 205/65-R15).

 

so 205/55 16 would be better for my 16" wheels? if true thats great cuz i cant find anybody selling good used tires for 205/40 16

 

Check the sticker in the driver's door jamb, for the STOCK size tires (in case I'm wrong about that).
Look at tire specs at someplace like tirerack.com to match the outer tread diameter.

I'm surprised the rims had 40-series tires, those might have been for an earlier Accord, like maybe '92... ?

 

Stock tire size is 195/65R15. Use miata.net/garage/tirecalc.html to compare sizes. 205 and 225 tires are a lot easier to find (and cheaper) than 215.