well if you aren't trying to do a PIVOT TABLE
and can't do this in another programming language (which would be the best options for this)... something you can do is this.
SELECT
t.prodID,
t1.seller1,
t.seller2,
t2.seller3,
t3.seller4,
t4.seller5
FROM
(
SELECT
m1.prodID, m1.price AS seller2
FROM myTable AS m1
WHERE m1.seller LIKE "seller2"
) AS t
LEFT JOIN
(
SELECT
m.prodID,
m.price AS seller1
FROM myTable AS m
WHERE m.seller LIKE "seller1"
) AS t1 ON t.prodID = t1.prodID
LEFT JOIN
(
SELECT
m2.prodID,
m2.price AS seller3
FROM myTable AS m2
WHERE m2.seller LIKE "seller3"
) AS t2 ON t2.prodID = t.prodID
LEFT JOIN
(
SELECT
m3.prodID,
m3.price AS seller4
FROM myTable AS m3
WHERE m3.seller LIKE "seller4"
) AS t3 ON t3.prodID = t.prodID
LEFT JOIN
(
SELECT
m4.prodID,
m4.price AS seller5
FROM myTable AS m4
WHERE m4.seller LIKE "seller5"
) AS t4 ON t4.prodID = t.prodID
this is kinda a hacky way to do it, but it transposes your data per your request. see the sql fiddle for results... http://sqlfiddle.com/#!2/55f59/45