Or you could use the soft serial lib.
Although it isn't important with respect to receive-only devices like many serial LCDs, it should be noted that the soft serial lib has a couple of shortcomings that may or may not be significant for other applications. Firstly, the "software UART" is half duplex meaning that it can be transmitting or it can be receiving but it can't do both at the same time. Secondly, correct reception only occurs if you invoke SWread() before the external device begins sending. Data sent at other times is missed.
It is possible to implement full duplex software UART, even one with multiple channels. We implemented a full duplex software UART for the ZBasic chips that supports up to 4 simultaneously operating channels that are fully buffered. It uses a timer interrupt to detect the start bit and to regulate both the transmit and receive timing.
Also, you can find AVR code for a software UART that implements the receive side using an external interrupt or pin change interrupt to detect the start bit and a timer to regulate the receive timing. Code like this would handle external serial devices that send data spontaneously.