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I am re-designing a existing fast Ethernet MAC IP... which needs to be fit in to Altera's small FPGA which should be optimized in both speed and area. I would like to reduce its size to round about less than 1000 LEs and 4-6 Kb internal memory usage.
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In the Quartus handbook, see Volume 2, Section III, "Area, Timing and Power Optimization".
Within Quartus, run "Resource Optimization Advisor" and "Timing Optimization Advisor" at "Tools --> Advisors".
Note that some optimizations that help area hurt speed and vice versa.